High school geography instruction often simplifies the heat-retention effect of temperature inversions into a universally applicable principle, yet the winter case study of the Yinchuan Plain reveals the limitations of this understanding. By analyzing a real-world case where the heat-retention eff ect was limited and led to dense fog, this article aims to shift the focus of instruction from rote memorization to an exploration of the boundaries of geographical principles. The study fi nds that current geography education must move beyond the misconception of“generalizing case studies”and shift toward “localized verification of principles.” Through data comparison and a progressive, three-stage inquiry-based teaching approach, students are guided to analyze the boundaries of geographical principles’applicability, thereby cultivating critical thinking and geography praxis, and off ering new insights for overcoming the challenges of teaching based on generalized case studies.